目前所选题目适合小学高年级学生。

In a dog race, my dog finished 4th best (which was also 4th from last). If there were 2 ties (3 dogs in the same place in each tie), how many dogs ran in this race?

A) 9   B) 10    C) 11    D) 13

参考答案：C

解析：tie，平局，并列

如果没有并列，那么应该是7只狗狗，因为有两个名次是三只狗狗并列，这两个位置各多出两只狗狗，因此，一共是11只狗狗。

Devi has a wooden cube with 3 inches on each edge. She painted red on all the faces and then cut it into small 1-inch cubes. What is the ratio of the small cubes that have exactly one face painted red to the small cubes that have exactly 2 faces painted red?

A) 1 : 6    B) 3 : 4   C) 1 : 2    D) 2 : 1

参考答案:C

解析：只有一个面是红色的只能是大正方形每个面中间部分切割出来的，大正方形有六个面，因此是六个。有两个面是红色的，是大正方形每条边中间部分切割出来的，大正方形有十二条边，因此是十二个，所以比例是1比2。

What is the quotient when 3^9 is divided by 9^3 ?

A) 3 ÷3    B) 32   C) 3 ×9    D) 3 + 9

参考答案：C

解析：9^3=(3^2)^3=3^6，3^9÷9^3=3^9÷3^6=3^(9−6)=3^3=3×3×3=3×9

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